Not Applicable
Not Applicable
The present invention generally relates to seat track assemblies allowing for adjustment of a seat with respect to a fixed member and, more particularly, to seat track assemblies suitable for adjusting the position of a seat with respect to a motor vehicle.
Numerous seat track assemblies are used in the automotive industry to adjust the position of a seat in at least fore and aft directions with respect to a motor vehicle. Typically automotive seats have a seat back and a seat base, and the seat track assembly connects the seat base to a floor of the motor vehicle. U.S. Pat. No. 5,855,350 is owned by an affiliated corporation of the assignee of the present invention, and the disclosure of which is expressly incorporated herein in their entirety by reference, discloses an example of a so-called horizontal seat track assembly. In these kinds of seat track assemblies, the lateral stabilization ball bearing raceways are aligned so as to be generally parallel with the seat base and the floor of the motor vehicle. In such known horizontal seat track assemblies it has been desired to make the tracks more and more rigid to resist rattle, particularly when the seat track assembly is subject to a light load (e.g., when the seat is unoccupied). However, it has been found to be difficult to hold tolerances on the horizontal seat tracks when more rigid materials are used. This in turn makes it difficult to provide a raceway that maintains four point contact with ball bearings consistently along the travel path of the tracks. Other manufacturers sometimes have such difficulty holding tolerances on such tracks that they have to hold bearings of varying diameter in stock, make the tracks, then determine the size of the bearing raceway and insert bearings of the appropriate diameter.
U.S. Pat. No. 6,145,914, owned by the assignee of the present invention, and the disclosure of which is expressly incorporated herein in its entirety by reference, discloses an example of a so-called vertical seat track assembly. In these kinds of seat track assemblies, the load bearing elements are positioned vertically with respect to the seat base and the floor of the motor vehicle. The vertical seat track assemblies do not always function well when aligned horizontally. In some designs, the interlocking nature of the tracks (to help resist dislocation if the tracks are subjected to vertical dislocation forces) is uni-directional. That is, there is no interlocking feature to resist vertical dislocation if the tracks are positioned in the wrong orientation. It has become desirable to have a universal seat track assembly which can be positioned either horizontally or vertically, depending on the customer""s space and packaging needs as well as other design requirements.
In view of the foregoing, it is an aspect of the present invention to provide a universal seat track assembly for use in a motor vehicle to provide for at least fore and aft adjustment of a seat of a motor vehicle, whether design constraints mandate a horizontal configuration or a vertical configuration. It is an additional aspect of the present invention to provide a seat track assembly which enhances manufacturability and which provides consistent low efforts for comfort adjustment of a motor vehicle seat. It is yet another aspect of the present invention to provide a seat track assembly that is highly reliable in operation.
In accordance with one aspect of the present invention, a seat track comprises, in combination, a first track having a mounting wall and first and second spaced-apart side walls extending along the mounting wall, and a second track movable relative to the first track and having a base flange and first and second spaced-apart side flanges extending along the base flange. The first side wall forms first and second surfaces, the first side flange forms third and fourth surfaces, and the first, second, third, and fourth surfaces cooperate to define a first load transmission channel. At least one first load transmission element is located within the first load transmission channel. At least one of the first track and the second track is configured to produce an interference between the at least one first load transmission element and at least one of the first track and the second track so that at least one of the first track and the second track is resiliently deflected by the at least one first transmission element to bias the at least one first load transmission element into engagement with each of the first, second, third, and fourth surfaces.
In accordance with another aspect of the present invention, a seat track assembly comprises, in combination, a first track having a mounting wall and first and second spaced apart side walls extending along the mounting wall, and a second track movable relative to the first track and having a base flange and first and second spaced apart side flanges extending along the base flange. The first side wall forms first and second flat surfaces, the first side flange forms third and fourth flat surfaces, and the first, second, third, and fourth flat surfaces cooperate to define a first load transmission channel. At least one first load transmission element is located within the first load transmission channel. At least one of the first track and the second track is configured to produce an interference between the at least one first load transmission element and at least one of the first track and the second track so that at least one of the first track and the second track. is resiliently deflected by the at least one first transmission element to bias the at least one first load transmission element into engagement with each of the first, second, third, and fourth flat surfaces. The second side wall forms fifth and sixth flat surfaces, the second side flange forms seventh and eighth flat surfaces, and the fifth, sixth, seventh, and eighth flat surfaces cooperate to define a second load transmission channel. At least one second load transmission element located within the second load transmission channel. At least one of the first track and the second track is configured to produce an interference between the at least one second load transmission element and at least one of the first track and the second track so that at least one of the first track and the second track is resiliently deflected by the at least one second transmission element to bias the at least one second load transmission element into engagement with each of the fifth, sixth, seventh, and eighth flat surfaces.
From the foregoing disclosure and the following more detailed description of various preferred embodiments it will be apparent to those skilled in the art that the present invention provides a significant advance in the technology and art of seat track assemblies. Particularly significant in this regard is the potential the invention affords for providing a high quality, reliable, low cost universal assembly. Additional features and advantages of various preferred embodiments will be better understood in view of the detailed description provided below.